Resisting device.



" BNTED DEC. 1, 1903.

EVICE.

AUG. 6, 1902.

G. BAEHR.

RESISTING D APPLICATION' FILED No. 745,759. Patented December 1, 1903.

UNITED STATES PATENT OEEICE.

GEORGE BAEHR, OF IWICKEESPORT, PENNSYLVANIA, ASSIGNOR TO NATIONAL TUBE COMPANY, OF NEW YORK, N. Y., AND PITTSBURG AND MOKEES- PORT, PENNSYLVANIA, A CORPORATION OF NEW JERSEY.

RESISTING DEVICE.

SPECIFICATION forming part of Letters Patent No. 745,759, dated. December 1, 1903.

' Application tiled August 6, 1902. Serial No. 118,562. (No model.)

To a/ZZ whom it may concern: material,such as asbestos or the like,and wind Be it known that I, GEORGE BAEHR, a resithe two together in spiral form. In this mandent of McKeesport, in the county of Allener a continuous spiral conductor is formed, gheny and State of Pennsylvania, have inthe coils of which are thoroughly insulated 5 vented a new and useful Improvement in from each other. The ends of this conductor 55 Resistance Devices; and I do hereby declare are connected to the terminal-pieces S and 9. the following to be a full, clear, and exact The strip or ribbon of insulating material 11 description thereof. will be somewhat wider than the strip or rib- My invention relates to electric resistance bon of conducting material, so that its edges o devices; and its Objectis to provideadevice of will project beyond the edges of said conduc- 6o this kind com posed of a number of units each tor, as shown in Fig. 13, thus preventing any of which is very simple and cheap to make and leakage of the current around the edges of so arranged that any number can be easily the insulating` material. arrangedin proper position and order and the The units constructed as above described l5 circuit connections thereto changed with ease. can be readily assembled in any quantity or 65 In the accompanying drawings, Figure 1 is in any order by merely passing a rod 13 therean elevation showing a stand with a number through, four such rods being shown in Fig. 1 of my resistance devices therein. Fig. y2 is a and being mounted in a suitable frame 14. face View of one of the units thereof, and Fig. To furtherguard against short-circuiting, the Y zo 3 is a section therethrough. units will be insulated from the rods 13 by a 7o r Each of the resistance units comprises a layer of asbestos or the like l5 and by mica frame or casing 1, which is somewhat pan- Washers insulating` each unit from the adjashaped, having a rim 2, and the bottom either cent one. The units preferably will be asbeingsolid,butpreferablyperforated, orcomsembled in pairs, as indicated in Fig. 1, the 25 posed of a series of bars, as indicated in Fig. members oi' each pair facing each other, and 75 2, said pan being` provided with the perforated the outside members of each pair being back central h ub 4L. This frame or casing is preferto back to the similar member of the next ably made of cheap cast metal. The bottom adjacent pair. The connections can then be thereofis lined withalayer ofinsulating matevery easily made between the central termi- 3o rial 5,such as asbestos or the like,and inside the nals of facing pairs and the outside lter- 8o frame is also placed a layer of insulating maminals of the pairs placed back to back, as terial 6, such as mica or the like. The hub shown in Fig. 1. The wires 17 leading to the 4f is also surrounded by a sleeve of insulating contacts of the switchboard can be connectmaterial '7, such as asbestos or the like. The ed in any manner by merely inserting them 35 terminals or contact-pieces are shown at 8 viu the bindingpost of any one of the termi- 85 and 9.v They are formed of metal, the former nal-pieces of the units, and whenever it is being segmental in shape, as shown in Fig. 2, desired to alter the resistance it is a simple and lies just inside of the insulating-ring 6, matter to change these connections, as it 7 whereas the latter is of sleeve form surroundmerely necessitates the taking out of lthe wire 4o ing theinsulating material 7.V Each terminalfrom one terminal-piece and inserting it in 9o piece is provided with a suitable binding-post another. for the connection of the Wires. These ter- The resistance device described is exceedminals are connected bya continuous condncingly simple, cheap to make, and cannot tor 10, which preferably is in the form of a readily get out of order, and the units are so 45 thin strip or ribbon of metal wound in spiral assembled that connection therebetween and 95 form, asshoWn-in Fig. 2, and having the coil to the switchboard can be very quickly and i separated by suitable insulating material. A easily made.

cheap and convenientway of forming this coil What I claim is is to take astrip or ribbon of sheet metal, lay 1. A resistance unit comprising a frame 5o the same upon a strip or ribbon of insulating having hub and a rim, metallic terminalroo pieces located respectively at the rim and at the hub and insulated therefrom, and a conductor connecting said terminal-pieces, said conductor being formed from a metal strip Wound into spiral form and having the coils thereof separated by a strip of insulatingmaterial Wider than the conducting-strip.

2. A resistance device comprising a frame having a hub and a rim, a lining of insulating material for said frame, metallic terminalpieces located respectively at the rim and at the hub inside of the insulated lining, a conductor connecting said terminals, said conductorcomprisingastrip ofsheetinetalwound in spiral form and having the coils separated by a strip of insulating material wider than the conducting-strip.

3. A resistance device comprising a plurality of units each comprising a frame having a rim and a perforated hub, terminal-pieces located respectively at the rim and hub and insulated from the frame, and a conductor connecting said terminal-pieces, said conductor comprising a metal strip Wound into spiral form and having the coils insulated from each other and from the frame, a rod passing through the perforated hubs of a number of said units, and insulating material between said rod and said hubs.

et. A resistance device comprising a plurality of nuits each comprising a frame having a perforated hub and a rim, terminal-pieces located respectively at the rim and at the hub and insulated from the frame, and a conductor connecting said contact-pieces, said conductor comprising a spirally-wound metal strip having` its coils insulated from each other and from the frame, a rod passing through the hubs of said units, said units being arranged in pairs facing each other, and electrical connections between the central terminal-pieces of facing units and between the outside terminal-pieces of units placed back to back.

In testimony whereof I, the said GEORGE BAEHR, have hereunto set my hand.

GEORGE BAEHR. Vitnesses:

A. M. STEEN, G. C. RAYMOND. 

